It’s not just extreme conditions that manufacturers worry about when packaging and shipping products. Even the most durable materials are vulnerable to the elements, including oxygen.
The principle of oxidative degradation shows us that prolonged exposure to oxygen can cause irreparable damage to certain materials, which compound with other conditions. This can eat into profits for companies as they look to maximize efficiency in shipping, storage, shelf-life, and consumer satisfaction.
Let’s explore what oxidative degradation is, how it works, impacts various materials, and what manufacturers can do to combat these problems with better products and practices with Dymapak.
What Is Oxidative Degradation?
We generally give positive associations to oxygen, from breathing clean air to facilitating plant and animal life. But oxygen goes from friend to enemy in a flash when generating and preserving polymers and other materials for market-ready products.
This is due to oxygen’s ability to induce free radicals in various polymer compounds, from rubber and wool to proteins and even cellular structures found in our bodies. That’s why doctors advocate “antioxidant” vitamins and minerals to fight against the impact of oxidation on a cellular level and preserve our long-term health.
The actual process of oxidative degradation looks something like this:
- The oxidizing agent (in this case, oxygen) is exposed to the polymer
- Electrons are pulled from the molecule during a chemical reaction
- The oxidation state of the molecule is increased, changing its properties
- These reactions can be rapid or take many months or years to complete
A classic example of oxidation can be seen when iron combines with oxygen to form iron oxide, better known as rust. At a chemical level, oxygen is pulling electrons from the iron molecules, altering their physical composition and reducing (weakening) their physical properties.
It’s also worth noting that oxygen is not the only element that can cause oxidation. It’s simply the most common and referred to by its name. Other gasses and materials can alter chemical structures by reducing electron counts, which meets the technical definition of oxidation on all counts.
For some synthetic polymers, the effects of oxidation can be immediate and extreme, given the sensitive nature of these artificial materials. Early forms of plastic were vulnerable to oxygen, especially with the concurrent effects of heat and light.
Modern polymers, conversely, are explicitly designed to protect against oxidation and even create strong barrier properties that keep oxygen from crossing into the interior of a package. This is ideal for prolonging the shelf life of food and pharmaceutical products, even after long supply chain journeys.
Are Oxidation and Degradation the Same Thing?
Degradation is a broad category of possible effects on polymers and plastics, induced by everything from chemicals and heat to mechanical friction or the recycling process.
Therefore, oxidation and degradation are not the same thing, since oxygen exposure doesn’t always necessitate the reduction in physical properties associated with a degraded state.
Instead, oxidative degradation is a type of damage incurred by materials that specifically result from exposure to oxygen and that alone. Since oxygen is rarely the only element in question (heat, light, and others are at play), it’s difficult to determine the precise effects of oxidative degradation in complex shipping and storage processes.
Still, enough evidence has been gathered to suggest that oxidative degradation is real and a greater concern for certain materials and applications.
This has led manufacturers and packaging industry leaders to create more resilient, stable materials that withstand the impact of oxygen throughout the product life cycle.
As polymer properties continue to improve, the impact of oxidation proves less of a threat, though it remains an important consideration in packaging and product design.
What Does Oxidation Do to Plastic?
With thousands of known plastic variations, oxidation will have varying effects based on the chemical structure of the materials and the presence of other conditions such as heat, light, moisture, and gaseous elements.
Here are some of the ways that oxidation can affect plastics and cause issues for manufacturers as they bring packaged products to market:
Hardening
Materials may become stiff and less movable with exposure to oxygen, limiting flexibility and sometimes preventing the user from using the product as intended.
Softening
Structural degradation often results in a softer, less resilient material, leading to packaging breaking apart and ruining products within.
Discoloration
Color changes may not impact the actual quality of the product, but buyers and consumers may report damaged products as the visual appeal and branding could be compromised.
In short, oxidation can ruin products that otherwise have all the right properties and features that consumers want. From packaging problems to the degradation of the product itself (food, medicine, tech components), oxidation is never a good thing for plastics and should be prevented at all costs.
What Is Thermo Oxidative Degradation of Plastic?
When oxidation is combined with extreme temperatures (usually high heat), plastics may see a reduction in properties in a process known as thermo- or thermal-oxidative degradation.
On their own, oxidation and thermal exposure each have different effects on plastics, combined and compounded to cause further degradation. While oxidation changes the chemical structure by removing electrons, heat can deteriorate properties by breaking covalent bonds and resulting in functional breakdowns of materials.
This becomes a point of focus for manufacturers as they look for the most resilient, effective materials to package and market products that must endure long supply chain journeys.
Companies must now seek out polymers that are not only resistant to oxidation but can also withstand high heat, exposure to light, humid conditions, and other factors that may result in degradation and revenue loss.
How Can Oxidative Degradation Be Prevented?
Manufacturers and logistics firms aim to reduce elemental exposure when transporting goods to maintain the stability of products and secure profits, but these measures don’t always succeed.
The most effective way to prevent oxidative degradation is to use materials designed specifically for long-term strength, stability, and resilience when faced with oxidation conditions.
Now that packaging systems technology is so advanced and widespread, manufacturers can access a full range of materials and package types and minimize degradation effects.
There are often tradeoffs when choosing packaging solutions, with variables like durability, user-friendliness, and cost all in play. However, with more options, brands now have the advantage and can find cost-effective ways to meet their needs.
What Is Used To Prevent Oxidative Degradation?
Plastic producers have found numerous ways to strengthen polymers and limit the effects of oxidation with antioxidants, stabilizers, and more.
Layering and combining laminates and films can also work to create stronger oxygen barriers that are commercially viable without being too costly.
Basic polymers are no longer feasible for large-scale manufacturing and shipping demands, and we’re now seeing brands customize their packaging materials with precise specifications.
From size, shape, color, barrier properties, and many other variables, the power is in the hands of the manufacturer to package products as they envision.
Conclusion
Oxidation and thermal degradation are nothing to fear if you have the right materials for the job.
While it’s important to understand these reactions and the harm they can cause, the proper packaging approach will give you peace of mind at every level of the production and shipping process, including the end-user experience.
Sources:
Thermal-Oxidative Degradation of Polymers | Polymer Database
Find Out How the Polymer Degradation Process Happens | PolyExcel
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